<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<style>
    progress {
        width: 500px;
        height: 50px;
    }
</style>

    <progress value="0" max="100"></progress>
    <meter value="2" min="0" max="10"></meter>
    <label contenteditable="true">可修改的</label>
    <dialog >这是一个会话</dialog>
    <input list="cars"/>
    <datalist id="cars">
        <option value="BMW"></option>
        <option value="ford"></option>
        <option value="volvo"></option>
    </datalist>
<br>
<svg xmlns="http://www.w3.org/2000/svg" version="1.1" height="190">
    <polygon points="100,10 40,180 190,60 10,60 160,180"
             style="fill:lime;stroke:purple;stroke-width:5;fill-rule:evenodd;" />
</svg>
<br>
<canvas id="myCanvas" width="200" height="100" style="border:1px solid #c3c3c3;">
    Your browser does not support the canvas element.
</canvas>
<br>
<input type="datetime-local" name="" id="">
<br>
<u>下划线</u>
    <script>
        var timer = setInterval(function () {
            var pro = document.querySelector('progress');
            if(pro.value == pro.max){
                clearInterval(timer);
            }else{
                pro.value += 1;
            }
        });
        var label = document.querySelector('label');
        var c=document.getElementById("myCanvas");
        var cxt=c.getContext("2d");
        var grd=cxt.createLinearGradient(0,0,175,50);
        grd.addColorStop(0,"#FF0000");
        grd.addColorStop(1,"#00FF00");
        cxt.fillStyle=grd;
        cxt.fillRect(0,0,175,50);

        var a =[];
        a[0]=1;a[1]=1;a[2]=1;a[5]=1;
        console.log(!![]);
        console.log(NaN == NaN);
        console.log(null == undefined);
    </script>
</body>

</html>